The consequences of this poisoning happen gradually. Over the long term, smoking leads people to develop health problems like heart disease, stroke, emphysema (breakdown of lung tissue), and many types of cancer — including lung, throat, stomach, and bladder cancer. People who smoke also have an increased risk of infections like bronchitis and pneumonia.
These diseases limit a person's ability to be normally active, and they can be fatal. In the United States, smoking is responsible for about 1 out of 5 deaths.